Unit 4 Genetics Summative Review (Adv)

Genetics

The branch of biology that deals with heredity and variation in organisms.

Alleles

Different versions of a gene that may produce distinguishable phenotypic effects.

Chromosomes

Structures within cells that contain DNA and carry genetic information.

Genetic Mutation

A change in the DNA sequence that can lead to changes in traits.

Karyotype

A visual representation of an individual's chromosomes, used to examine chromosomal abnormalities.

DNA

Deoxyribonucleic acid, the molecule that carries genetic instructions used in growth, development, and reproduction.

RNA

Ribonucleic acid, a molecule involved in protein synthesis and the transmission of genetic information.

mRNA

Messenger RNA, a type of RNA that carries genetic information from the DNA to the protein-making machinery.

tRNA

Transfer RNA, a type of RNA that transports amino acids to the ribosome during protein synthesis.

rRNA

Ribosomal RNA, a type of RNA that makes up the major part of ribosomes.

Sexual Reproduction

A type of reproduction that involves the combination of genetic material from two parents, leading to genetic diversity.

Asexual Reproduction

A type of reproduction that involves a single parent and produces offspring that are genetically identical to the parent.

Dominant Allele

An allele that expresses its trait even in the presence of a recessive allele.

Recessive Allele

An allele that only expresses its trait if there are two copies present.

Monohybrid Cross

A genetic cross between parents that differ in a single trait.

Phenotype

The observable physical characteristics of an organism as determined by both genetic makeup and environmental influences.

Genotype

The genetic makeup of an individual organism.

Pedigree

A chart shows how traits are passed down through generations; used to study inheritance patterns.

Codominance

A phenomenon where both alleles in a heterozygote are fully expressed.

Incomplete Dominance

A genetic situation where one allele does not completely dominate another allele, resulting in a new phenotype.

Mendel's Law of Segregation

Mendel's Law of Segregation says that when organisms make eggs or sperm, their two versions of a gene split apart. This means each egg or sperm only gets one version of the gene.

Mendel's Law of Independent Assortment

This law states that genes for different traits are passed down from parents to offspring independently. This means that the inheritance of one trait doesn't affect how another trait is inherited.

Natural Selection

Natural selection is the process where organisms with traits that are better suited to their environment tend to survive and reproduce, passing those traits to the next generation.

Selective Breeding (Artificial Selection)

Selective breeding, also known as artificial selection, is when humans choose which plants or animals to breed based on desired traits, like size or color.

Reasons for Selective Breeding

People selectively breed plants and animals to enhance specific traits, such as higher crop yields, better flavor, or specific appearances in pets.

Genotypic Ratio

The genotypic ratio tells us how many different gene types (genotypes) are in the offspring. For example, in a cross between a homozygous tall plant (TT) and a heterozygous tall plant (Tt), the genotypic ratio would be 1 TT : 1 Tt.

Phenotypic Ratio

The phenotypic ratio shows us how many different physical traits (phenotypes) appear in the offspring. For example, if we cross a homozygous tall plant (TT) with a homozygous short plant (tt), the phenotypic ratio would be 100% tall plants to 0% short plants.

What are the nitrogen bases in DNA?

The nitrogen bases in DNA are Adenine (A), Thymine (T), Cytosine (C), and Guanine (G). These bases pair together: A with T, and C with G.

What are the nitrogen bases in RNA?

The nitrogen bases in RNA are Adenine (A), Uracil (U), Cytosine (C), and Guanine (G). In RNA, Uracil replaces Thymine from DNA.